Butadiene such as 1,3-butadiene is used as a raw material of styrene-butadiene rubber (SBR) or the like. In general, butadiene is purified from a C4 fraction which is produced as a by-product when ethylene is synthesized from petroleum.
However, recently, bioethanol synthesized from a biomass-derived raw material has attracted attention as an alternative raw material to petroleum. For example, PTL 1 discloses a method of producing butadiene from ethanol using a catalyst.
However, in the method of obtaining butadiene from ethanol using the catalyst as in PTL 1, the yield is not industrially sufficiently high.